You de-legimitize yourself by even bothering to respond to such logic. Assume for a moment that the US has, over its 230 year existence, opposed Muslims (oppressed in their parlance) to the extent that, say India, has. You know, a couple of million or so killed during/after the 1948 partition.
Would such prior actions justify (or help explain) the acts of violence we're seeing today? And, as Victor David Hansen astutely pointed out, how come we don't see any retaliation against India?
The very idea that the US is to blame was merely a trial-ballon sent up to test the market response. In a pre-PC world, it would have been laughed at as no different from something uttered from Tokyo Rose.
But the muzzies got lucky because the US hating left provided them a willing and receptive audience. The muzzies don't believe it any more than the left; it merely satisifies both of their conditions for hating the West.